write some unit tests

test/main.c

@@ -1,20 +1,64 @@
 // Copyright (c) 2025 Quinn
 // Licensed under the MIT Licence. See LICENSE for details
+#include <math.h>
+#include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
 
+#include "../src/util/colour32.h"
+#include "../src/util/compat/endian.h"
+#include "../src/util/vec/float3.h"
 #include "test.h"
 
+static int test_float3_norm(void* d) {
+	float* arg = d;
+	float3 v = {arg[0], arg[1], arg[2]};
+	float3 r = float3_norm(v);
+	float n = r.x * r.x + r.y * r.y + r.z * r.z;
+
+	// check if the value is within 1 millionth of the one we expect
+	return assert_true(fabsf(n - 1.0F) < 1e-6F);
+}
+
+static int test_colour32_endianess(void* d) {
+	(void)d;
+	colour32 c = {0xFF000000}; // setting just the red channel
+	return assert_true(c.ch.r == 0xFF);
+}
+
+static int test_compat_endianess(void* d) {
+	uint32_t x = *((uint32_t*)d + 0);
+	int res = 0;
+
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+	res |= assert_false(be32ton(x) == x);
+	res |= assert_false(ntobe32(x) == x);
+	res |= assert_true(be32ton(ntobe32(x)) == x);
+	res |= assert_true(le32ton(x) == x);
+	res |= assert_true(ntole32(x) == x);
+#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+	res |= assert_false(le32ton(x) == x);
+	res |= assert_false(ntole32(x) == x);
+	res |= assert_true(le32ton(ntole32(x)) == x);
+	res |= assert_true(be32ton(x) == x);
+	res |= assert_true(ntobe32(x) == x);
+#else
+	res |= assert_false("platform unsupported!!");
+#endif
+	return res;
+}
+
 int main(void) {
-	/*
 	// tests that should be performed
 	testdat tests[] = {
+		{&test_float3_norm,        &(float3){2.0F, 0.67F, 5.0F}},
+		{&test_float3_norm,        &(float3){0.2F, 0.4F, 0.1F} },
+		{&test_colour32_endianess, (uint32_t[]){0, 1}          },
+		{&test_compat_endianess,   (uint32_t[]){0x15F59267}}
 	};
 
 	// get test count
 	size_t n = sizeof(tests) / sizeof(tests[0]);
-	*/
 
-	return exec_tests(NULL, 0);
-	// return exec_tests(tests, n);
+	return exec_tests(tests, n);
 }